Article of footwear with midsole having varying hardness

Abstract

The article of footwear may include an upper, a heel region having a heel core and a heel perimeter, a forefront region, a medial side, a lateral side, an outsole and a midsole. The midsole may be a dual durometer midsole and include a soft durometer positioned between the heel region and the forefoot region and a firm durometer positioned around the heel perimeter.

The invention claimed is: 
     
       1. An article of footwear comprising:
 an upper; 
 a heel region; 
 an external heel counter positioned around the heel region; 
 a forefoot region; 
 a midfoot region; 
 a medial side extending from the forefoot region to the heel region; 
 a lateral side extending from the forefoot region to the heel region and opposite to and generally parallel to the medial side; 
 a dual durometer midsole comprising (i) a soft durometer portion positioned from the heel region to the forefoot region and (ii) a firm durometer portion positioned in the heel region under the external heel counter; 
 an outsole, wherein a portion of the outsole forms an A-shaped support frame extending over the external heel counter, wherein a top portion of the A-shaped support frame is positioned within a recess in the firm durometer portion of the midsole, the A-shaped support frame comprising a set of lateral or medial legs, wherein the set of lateral or medial legs is configured to extend from the firm durometer portion of the midsole and mate with a corresponding lateral and medial recess in the soft durometer portion of the midsole, wherein the set of lateral or medial legs includes a first leg extending to the heel region and a second leg extending to the midfoot region, wherein the first leg and second leg are disposed at an angle to form an opening in the A-shaped support frame, wherein the opening is positioned below the external heel counter; and 
 a stability insert positioned at the midfoot region at a lateral side, a medial side, or both the lateral and medial sides. 
 
     
     
       2. The article of footwear of  claim 1 , wherein the soft durometer portion, the firm durometer portion, the A-shaped support frame, and the stability insert comprise a thermoplastic material selected from the group consisting of ethylene-vinyl acetate, polyurethane, and blends thereof. 
     
     
       3. The article of footwear of  claim 1 , wherein the soft durometer portion has a Shore C hardness between about 50 to 85, and wherein the firm durometer portion has a Shore C hardness between about 60 and 95. 
     
     
       4. The article of footwear of  claim 1 , wherein the external heel counter further includes ridges. 
     
     
       5. The article of footwear of  claim 1 , wherein the external heel counter is positioned above the firm durometer portion. 
     
     
       6. The article of footwear of  claim 1 , wherein the stability insert is configured to reduce sidewall movement during a golf swing. 
     
     
       7. The article of footwear of  claim 1 , wherein the firm durometer portion of the dual durometer midsole is U-shaped or horseshoe-shaped. 
     
     
       8. The article of footwear of  claim 1 , wherein the stability insert is connected to at least one of the soft durometer portion and the firm durometer portion. 
     
     
       9. The article of footwear of  claim 1 , wherein the stability insert comprises a lateral stability insert and a medial stability insert molded together with the firm durometer portion. 
     
     
       10. The article of footwear of  claim 9 , further comprising an internal or external bridge section connecting the lateral stability insert, the medial stability insert, and the firm durometer portion. 
     
     
       11. The article of footwear of  claim 1 , wherein the A-shaped support frame is (i) molded to the outsole or (ii) part of the outsole. 
     
     
       12. The article of footwear of  claim 1 , wherein the A-shaped support frame is configured to extend along at least a portion of the upper. 
     
     
       13. The article of footwear of  claim 1 , wherein the A-shaped support frame is configured to extend upwards from the midsole towards the upper. 
     
     
       14. The article of footwear of  claim 1 , wherein the A-shaped support frame comprises one or more sloped or slanted sidewalls. 
     
     
       15. The article of footwear of  claim 1 , wherein the A-shaped support frame extends over both the medial side and the lateral side of the upper. 
     
     
       16. The article of footwear of  claim 1 , wherein the opening has a predetermined shape with a fixed geometry. 
     
     
       17. The article of footwear of  claim 1 , wherein the midsole comprises (i) a first recess for receiving the first leg of the A-shaped support frame, wherein the first recess extends along the firm durometer portion of the midsole and (ii) a second recess for receiving the second leg of the A-shaped support frame, wherein the second recess extends along the soft durometer portion of the midsole. 
     
     
       18. The article of footwear of  claim 17 , wherein the first leg is configured to extend along the firm durometer portion of the midsole, and wherein the second leg is configured to extend along the soft durometer portion of the midsole. 
     
     
       19. The article of footwear of  claim 18 , wherein the second recess is configured to extend along a portion of the firm durometer portion that is in contact with the soft durometer portion so that the second leg extends along or across both the firm durometer portion and the soft durometer portion. 
     
     
       20. The article of footwear of  claim 1 , wherein the A-shaped support frame is configured as a support frame with a predetermined shape and geometry.